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                                                                    Exhibit 10.1

                                  EGENERA, INC.

                              AMENDED AND RESTATED
                      2000 STOCK OPTION/STOCK ISSUANCE PLAN

     1.   Purpose. This 2000 Stock Option/Stock Issuance Plan (the "Plan") is
intended to promote the interests of Egenera, Inc. by giving incentives to the
eligible officers and other employees and directors of and consultants and
advisors to Egenera, Inc. (the "Company"), its parent (if any) and any present
or future subsidiaries of the Company (collectively, "Related Corporations")
through providing opportunities to acquire stock in the Company. As used herein,
the terms "parent" and "subsidiary" mean "parent corporation" and "subsidiary
corporation", respectively, as those terms are defined in Sections 424(e) and
424(f) or successor provisions of the Internal Revenue Code of 1986 as amended
from time to time (the "Code").

     2.   Structure of the Plan. The Plan permits the following separate types
of grant:

     A. Options may be granted hereunder to purchase shares of common stock of
the Company. These options may meet the requirements of Section 422 of the Code
("Incentive Stock Options" or "ISOs"); or, they may not qualify as ISOs
("Non-Qualified Options"). Both ISOs and Non-Qualified Options are sometimes
referred to hereinafter as "Options".

     B. Awards of stock in the Company ("Awards") may be granted.

     C. Opportunities to make direct purchases of stock in the Company
("Purchases") may be authorized.

Options, Awards and authorizations to make Purchases are sometimes referred to
hereinafter as "Stock Rights".

     3.   Administration of the Plan.

     A. The Plan shall be administered by the Board of Directors of the Company
(the "Board"). The Board may in its sole discretion grant Options, authorize
Purchases and grant Awards, as provided in the Plan. The Board shall have full
power and authority, subject to the express provisions of the Plan, to construe
and interpret the Plan and all Option agreements, Purchase authorizations and
Award grants thereunder, to establish, amend and rescind such rules and
regulations as it may deem appropriate for the proper administration of the
Plan, to determine in each case the terms and provisions which shall apply to a
particular Option agreement, Purchase authorization, or Award grant, and to make
all other determinations which are, in the Board's judgment, necessary or
desirable for the proper administration of the Plan. The Board may correct any
defect, supply any omission or reconcile any inconsistency in the Plan or in any
Option agreement, Purchase authorization or Award grant in the manner and to the
extent it shall, in its sole discretion, consider expedient. Decisions of the
Board shall be final and

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binding on all parties who have an interest in the Plan or any Option, Purchase,
Award, or stock issuance thereunder. No director or person acting pursuant to
authority delegated by the Board shall be liable for any action or determination
under the Plan made in good faith.

     B. The Board may, to the full extent permitted by and consistent with
applicable law and the Company's By-laws, and subject to Subparagraph D
hereinbelow, delegate any or all of its powers with respect to the
administration of the Plan to a committee (the "Committee") appointed by the
Board. If a Committee has been appointed, all references in this Plan to the
Board shall mean and relate to that Committee.

     C. Those provisions of this Plan which make express reference to Rule 16b-3
under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), or
any successor rule ("Rule 16b-3"), or which are required in order for certain
option transactions to qualify for exemption under Rule 16b-3, shall apply only
to those persons required to file reports under Section 16(a) of the Exchange
Act (a "Reporting Person").

     D. If the Company registers any class of equity security under Section 12
of the Exchange Act, the selection of a director or an officer (as the terms
"director" and "officer" are defined for purposes of Rule 16b-3) as a recipient
of an option, the timing of the option grant, the exercise price of the option
and the number of shares subject to the option shall be determined either (i) by
the Board, if all of the Board members are disinterested persons within the
meaning of Rule 16(b)(3), or (ii) by two or more directors having full authority
to act in the matter, each of whom shall be such a disinterested person.

     4.   Eligible Employees and Others. ISOs may be granted to any employee of
the Company or of any Related Corporation. No person who is not such an employee
may be granted an ISO. Non-Qualified Options, Awards, and authorizations to make
Purchases may be granted to any employee, officer or director of, or consultant
or advisor to the Company or any Related Corporation. The granting of any Stock
Right to any individual or entity shall neither entitle that individual or
entity to, nor disqualify him from, participation in any other grant of Stock
Rights.

     5.   Stock. The stock subject to Options, Awards and Purchases shall be
authorized but unissued shares of common stock of the Company ("Common Stock"),
or shares of Common Stock reacquired by the Company in any manner. Subject to
adjustment as provided in Paragraph 14, the aggregate number of shares that may
be issued under the Plan is 15,250,000 shares of Common Stock. In no event shall
the number of shares subject to all Options, Awards or Purchases under the Plan
at the time of the grant of, and including the shares subject to, any Option,
Award or Purchase exceed 15,250,000 shares of Common Stock (as adjusted pursuant
to Paragraph 14) (a) less (i) the number of shares then subject to options
granted pursuant to the Company's 2001 California Stock Option/Stock Issuance
Plan (the "California Plan") and (ii) without duplication of any shares
described in the foregoing clause (i), the number of shares previously issued
pursuant to the exercise of any option granted, or award or purchase under the
California Plan, (b) plus the number of shares originally issued pursuant to the
exercise of any option granted, or award or purchase under the California Plan
or this Plan that are repurchased by the Company pursuant to contractual rights
held by the Company and at repurchase prices not

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exceeding the respective original purchase prices (or fair market value of such
shares as approved by the Board of Directors) paid by such persons to the
Company. If any option granted under the Plan or under the California Plan shall
expire or terminate for any reason without having been exercised in full or
shall cease for any reason to be exercisable in whole or in part, the
unpurchased shares subject to such Option or option shall again be available for
grants of Stock Rights under the Plan.

     6.   Option Agreements. As a condition to the grant of an Option, each
recipient of an Option shall execute an option agreement in such form not
inconsistent with the Plan as the Board shall approve. These option agreements
may differ among recipients. Each option agreement with respect to an ISO shall
be subject to the provisions of the Plan applicable to ISOs. The Board may, in
its sole discretion, include additional provisions in option agreements,
including without limitation restrictions on transfer, repurchase rights,
commitments to pay cash bonuses, to make, arrange for or guarantee loans or to
transfer other property to optionees upon exercise of options, or such other
provisions as shall be determined by the Board; provided, however, that such
additional provisions shall not be inconsistent with any provision of the Plan
and such additional provisions shall not cause any ISO granted under the Plan to
fail to qualify as an incentive stock option within the meaning of Section 422
of the Code.

     7.   Option Exercise Price.

     A. Subject to Subparagraph 3D of this Plan and Subparagraphs B and C of
this Paragraph 7, the purchase price per share of Common Stock deliverable upon
the exercise of an Option ("exercise price") shall be determined by the Board.

     B. In the case of an ISO, the exercise price shall not be less than 100% of
the fair market value of Common Stock, as determined by the Board, at the time
of grant of such option, or less than 110% of such fair market value in the case
of an ISO granted to the owner of stock possessing more than 10% of the total
combined voting power of all classes of stock of the Company or any Related
Corporation (after taking into account the attribution of stock ownership rules
of Section 424(d) of the Code) (a " 10% Shareholder").

     C. The exercise price of each Non-Qualified Option granted under the Plan
shall in no event be less than the lesser of (i) the book value per share of
Common Stock as of the end of the fiscal year of the Company immediately
preceding the date of grant, or (ii) thirty percent (30%) of the fair market
value per share of Common Stock on the date of grant.

     8.   Cancellation and New Grant of Options, Etc. The Board shall have the
authority to effect, at any time and from time to time, with the consent of the
affected optionees, (i) the cancellation of any or all outstanding Options and
the grant in substitution therefor of new Options covering the same or different
shares of Common Stock and having an exercise price per share which may be lower
or higher than the exercise price per share of the canceled Options, or (ii) the
amendment of the terms of any and all outstanding Options to provide an exercise
price per share which is higher or lower than the then-current exercise price
per share of such outstanding Options.

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     9.   Exercise of Options.

     A. Each Option granted under the Plan shall be exercisable either in full
or in installments at such time or times and during such period as shall be set
forth in the agreement evidencing the Option, subject to the provisions of the
Plan. An option agreement may permit the Option granted thereunder to be
exercised before it is vested (an "Early Exercise"), subject to the Company's
right of repurchase, under a Stock Restriction Agreement (as defined below) to
be executed by the option holder and the Company at the time of such Early
Exercise, over any shares acquired under the unvested portion of the Option,
which right of repurchase shall lapse at the same time the Option would have
vested had there been no Early Exercise. Unless doing so would have the effect
of causing an ISO to be treated as a Non-Qualified Option, the board may, in its
sole discretion, after consideration of such factors as it considers relevant
(which may include the impact, if any, on the Company's financial statements of
such change in the terms of the Option or Options), (i) accelerate the date or
dates on which all or any particular Option or Options granted under the Plan
may be exercised or (ii) extend the dates during which all, or any particular,
Option or Options granted under the plan may be exercised.

     B. Options granted under the Plan may provide for payment of the exercise
price by delivery of cash or a check payable to the order of the Company, or, to
the extent (if at all) provided in the option agreement: (i) by delivery to the
Company of shares of Common Stock of the Company already owned by the optionee
having a fair market value determined by the Board to be equal in amount to the
exercise price of the Options being exercised, or (ii) by delivery of a recourse
promissory note of the optionee bearing interest payable not less than annually
at the applicable Federal rate as defined in Section 1274(d) of the Code and
otherwise payable on such terms as are specified by the Board, or (iii) by
requesting that the Company withhold shares of Common Stock of the Company
issuable upon exercise of the Options having a fair market value determined by
the Board to be equal in amount to the exercise price of the Options being
exercised, or (iv) by any combination of the above methods of payment.

     10.  Option Period. Subject to earlier termination under other provisions
of this Plan, each Option and all rights thereunder shall expire on such date as
shall be set forth in the applicable option agreement, except that, in the case
of an ISO, such expiration date shall not be later than ten years after the date
on which the ISO is granted and, in the case of an ISO granted to a 10%
Shareholder as defined in Subparagraph 7B of this Plan, such expiration date
shall not be later than five years after the date on which the ISO is granted.

     11.  Nontransferability of Options. Options shall not be assignable or
transferable by the optionee, either voluntarily or by operation of law, except
by will or the laws of descent and distribution, and, during the life of the
optionee, shall be exercisable only by the optionee.

     12.  Effect of Termination of Employment or Other Relationship. Except as
otherwise provided in Paragraph 10 and Subparagraph 13C with respect to ISOs,
and subject to all other provisions of the Plan, the Board shall determine the
period of time during which an optionee may exercise an Option following (i) the
termination of the optionee's employment or other relationship with the Company
or a Related Corporation or (ii) the death or disability of the optionee. Such
periods shall be set forth in the agreement evidencing the Option.

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     13.  Additional ISO Requirements. ISOs granted under the Plan are subject
to the minimum exercise price rules set forth in Subparagraph 7B hereof, the
option period rules of Paragraph 10 hereof, and various other restrictions set
forth elsewhere in this Plan. In addition, ISOs granted under the Plan are
subject to the following:

     A . Each ISO granted under the Plan shall, at the time of grant, be
specifically designated as such in the option agreement evidencing such Option.

     B. In no event shall the aggregate fair market value (determined at the
time an ISO is granted) of Common Stock for which ISOs granted to any employee
are exercisable for the first time by such employee during any calendar year
(under all stock option plans of the Company and any Related Corporation) exceed
One Hundred Thousand Dollars ($100,000); provided, however, that this
Subparagraph B shall have no force or effect if its inclusion in the Plan is not
necessary for Options issued as ISOs to qualify as incentive stock options
within the meaning of Section 422 of the Code.

     C. No ISO may be exercised unless, at the time of such exercise, the
optionee is, and has been continuously since the date of grant of the ISO,
employed by the Company or a Related Corporation, except that:

          (i)  An ISO may be exercised within the period of three (3) months
     after the date the optionee ceases to be an employee of the Company and any
     Related Corporation (or within such lesser period as may be specified in
     the option agreement); provided, however, that the option agreement may
     designate a longer exercise period, in which case the exercise after such
     three-month period shall be treated as the exercise of a Non-Qualified
     Option.

          (ii) If the optionee dies while in the employ of the Company or a
     Related Corporation, or within three (3) months after the optionee ceases
     to be such an employee of the Company or a Related Corporation, the ISO may
     be exercised by the person to whom it is transferred by will or the laws of
     descent and distribution within the period of one (1) year after the date
     of death (or within such lesser period as may be specified in the option
     agreement).

          (iii) If the optionee becomes disabled (within the meaning of Section
     22(e)(3) of the Code) while in the employ of the Company or a Related
     Corporation, the ISO may be exercised within the period of one (1) year
     after the date the optionee's employment ceases because of such disability
     (or within such lesser period as may be specified in the option agreement).

For all purposes of the Plan and any agreement evidencing an Option,
"employment" shall be defined in accordance with the provisions of Treasury
Regulation Section 1.421-7(h) under the Code (or any successor regulations).
Notwithstanding the foregoing provisions, no ISO may be exercised after its
expiration date.

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     14.  Adjustments.

     A. If, through or as a result of any merger, consolidation, sale of all or
substantially all of the assets of the Company, reorganization,
recapitalization, reclassification, stock dividend, stock split, reverse stock
split or other similar transaction, (i) the outstanding shares of Common Stock
are increased, decreased or exchanged for a different number or kind of shares
or other securities of the Company, or (ii) additional shares or new or
different shares or other securities of the Company or other non-cash assets are
distributed with respect to such shares of Common Stock or other securities, an
appropriate and proportionate adjustment shall be made in (a) the maximum number
and kind of shares reserved for issuance under the Plan, (b) the number and kind
of shares or other securities subject to any then outstanding Options under the
Plan, and (c) the price for each share subject to any then outstanding Options
under the Plan, without changing the aggregate purchase price as to which such
Options remain exercisable. No fractional shares shall be issued under the Plan
on account of any such adjustments. Notwithstanding the foregoing provisions of
this Subparagraph A, no adjustment shall be made pursuant to this Paragraph 14
if such adjustment would cause any ISO granted under the Plan to fail to qualify
as an incentive stock option within the meaning of Section 422 of the Code.

     B. Any adjustments under this Paragraph 14 shall be made by the Board of
Directors, whose determination as to what adjustments, if any, will be made and
the extent thereof shall be final, binding and conclusive.

     15.  Rights as a Shareholder. The holder of an Option shall have no rights
as a shareholder with respect to any shares covered by the option (including,
without limitation, any voting rights, or any rights to receive dividends or
non-cash distributions with respect to such shares) until the date of issue of a
stock certificate for such shares. No adjustment shall be made for dividends or
other rights for which the record date is prior to the date such stock
certificate is issued.

     16.  Merger, Consolidation. Asset Sale, Liquidation. etc.

     A. Except as may otherwise be provided in the applicable option agreement,
in the event of a consolidation or merger or sale of all or substantially all of
the assets of the Company in which outstanding shares of Common Stock are
exchanged for securities, cash or other property of any other corporation or
business entity, or in the event of the liquidation of the Company, the Board,
or the board of directors of any corporation assuming the obligations of the
Company, shall, in its discretion, take any one or more of the following
actions, as to outstanding Options: (i) provide that such Options shall be
assumed, or equivalent options shall be substituted, by the acquiring or
succeeding corporation (or an affiliate thereof), provided, however, that any
such Options substituted for ISOs shall meet the requirements of Section 424(a)
of the Code; (ii) upon written notice to the optionees, provide that any and all
outstanding Options shall become exercisable in full (to the extent not
otherwise so exercisable) as of a specified date or time ("Accelerated Vesting
Date") prior to the consummation of such transaction, and that all unexercised
Options shall terminate as of a specified date or time ("Accelerated Expiration
Date") following the Accelerated Vesting Date unless exercised by the optionee
prior to the Accelerated Expiration Date, provided, however, that optionees
shall be given a reasonable

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period of time within which to exercise or provide for the exercise of
outstanding Options following such written notice and before the Accelerated
Expiration Date; (iii) in the event of a merger under the terms of which holders
of the Common Stock of the Company will receive upon consummation thereof a cash
payment for each share surrendered in the merger (the "Merger Price"), terminate
each outstanding Option in exchange for a payment, made or provided for by the
Company, equal in amount to the excess, if any, of the Merger Price over the
per-share exercise price of each such Option, times the number of shares of
Common Stock subject to such Option; or (iv) terminate each outstanding Option
in exchange for a cash payment equal in amount to the product of the excess, if
any, of the fair market value of a share of Common Stock over the per-share
exercise price of each such Option, times the number of shares subject to such
Option. The Board shall determine the fair market value of a share of Common
Stock for purposes of the foregoing, and the Board's determination of such fair
market value shall be final, binding and conclusive.

     B. The Company may grant Options under the Plan in substitution for Options
held by employees of another corporation who become employees of the Company or
a subsidiary of the corporation as the result of a merger or consolidation of
the employing corporation with the Company or a subsidiary of the Company, or as
a result of the acquisition by the Company or one of its subsidiaries of
property or stock of the employing corporation. The Company may direct that
substitute Options be granted on such terms and conditions as the Board
considers appropriate in the circumstances.

     17.  Stock Restriction Agreement. As a condition to the grant of an Award
or a Purchase authorization under the Plan, the recipient of the Award or
Purchase authorization shall execute an agreement ("Stock Restriction
Agreement") in such form not inconsistent with the Plan as may be approved by
the Board. Stock Restriction Agreements may differ among recipients. Stock
Restriction Agreements may include any provisions the Board determines should be
included and that are not inconsistent with any provision of the Plan.

     18.  No Special Employment Rights. Nothing contained in the Plan or in any
option agreement or other agreement or instrument executed pursuant to the
provisions of the Plan shall confer upon any optionee any right with respect to
the continuation of his or her employment by the Company or interfere in any way
with the right of the Company at any time to terminate such employment or to
increase or decrease the compensation of the optionee.

     19.  Other Employee Benefits. Except as to plans which by their terms
include such amounts as compensation, no amount of compensation deemed to be
received by an employee as a result of the grant or exercise of an Option or the
sale of shares received upon such exercise, or as a result of the grant of an
Award or the authorization or making of a Purchase will constitute compensation
with respect to which any other employee benefits of such employee are
determined, including, without limitation, benefits under any bonus, pension,
profit-sharing, life insurance or salary continuation plan, except as otherwise
specifically determined by the Board.

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     20.  Amendment of the Plan.

     A. The Board may at any time, and from time to time, modify or amend the
Plan in any respect, except as otherwise expressly provided in this Plan;
provided, however, that if at any time the approval of the shareholders of the
Company is required under the Code with respect to ISOs, or is required under
Rule 16b-3, the Board may not effect such modification or amendment without such
approval.

     B. The termination or any modification or amendment of the Plan shall not,
without the consent of an optionee, affect the optionee's rights under an Option
previously granted. With the consent of the optionee affected, the Board may
amend outstanding option agreements in a manner not inconsistent with the Plan.
The Board shall have the right to amend or modify (i) the terms and provisions
of the Plan and of any outstanding ISO granted under the Plan to the extent
necessary to qualify any or all such Options for such favorable federal income
tax treatment (including deferral of taxation upon exercise) as may be afforded
incentive stock options within the meaning of Section 422 of the Code, and (ii)
the terms and provisions of the Plan and of any outstanding Option to the extent
necessary to ensure the qualification of the Plan under Rule 16b-3.

     21.  Investment Representations. The Board may require any person to whom
an Option is granted, as a condition of exercising such Option, and any person
to whom an Award is granted or a Purchase is authorized, as a condition thereof,
to give written assurances in substance and form satisfactory to the Board to
the effect that such person is acquiring the Common Stock subject to the Option,
Award or Purchase for such person's own account for investment and not with any
present intention of selling or otherwise distributing the same, and to such
other effects as the Company deems necessary or appropriate in order to comply
with federal and applicable state securities laws, or with covenants or
representations made by the Company in connection with any public offering of
its Common Stock.

     22.  Compliance With Securities Laws. Each Option shall be subject to the
requirement that if, at any time, counsel to the Company shall determine that
the listing, registration or qualification of the shares subject to such Option
upon any securities exchange or under any state or federal law, or the consent
or approval of any governmental or regulatory body, or that the disclosure of
non-public information or the satisfaction of any other condition is necessary
as a condition of, or in connection with, the issuance or purchase of shares
thereunder, such Option may not be exercised, in whole or in part, unless such
listing, registration, qualification, consent or approval, or satisfaction of
such condition shall have been effected or obtained on conditions acceptable to
the Board. Nothing herein shall be deemed to require the Company to apply for or
to obtain such listing, registration or qualification, or to satisfy such
condition.

     23.  Withholding. The Company shall have the right to deduct from payments
of any kind otherwise due to the optionee any federal, state or local taxes of
any kind required by law to be withheld with respect to any shares issued upon
exercise of Options under the Plan or upon the grant of an Award, the making of
a Purchase of Common Stock for less than its fair market value, the making of a
Disqualifying Disposition (as defined in Paragraph 24), or the vesting of

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restricted Common Stock acquired pursuant to a Stock Right. The Board in its
sole discretion may condition the exercise of an Option, the grant of an Award,
the making of a Purchase, or the vesting of restricted shares acquired by
exercising a Stock Right on the grantee's payment of such additional withholding
taxes. Subject to the prior approval of the Company, which may be withheld by
the Company in its sole discretion, the grantee may elect to satisfy such
obligations, in whole or in part, (i) by causing the Company to withhold shares
of Common Stock otherwise issuable pursuant to the exercise of a Stock Right or
(ii) by delivering to the Company shares of Common Stock already owned by the
grantee. The shares so delivered or withheld shall have a fair market value
equal to such withholding obligation, and shall not be subject to any
repurchase, forfeiture, unfulfilled vesting or other similar requirements. The
fair market value of the shares used to satisfy such withholding obligation
shall be determined by the Company as of the date that the amount of tax to be
withheld is to be determined. Notwithstanding the foregoing, in the case of a
Reporting Person, no election to use shares for the payment of withholding taxes
shall be effective unless made in compliance with any applicable requirements of
Rule 16b-3 (unless it is intended that the transaction not qualify for exemption
under Rule 16b-3).

     24.  Notice to Company of Disqualifying Disposition. Each employee who
receives an ISO must agree to notify the Company in writing immediately after
the employee makes a Disqualifying Disposition, as hereinafter defined, of any
Common Stock acquired pursuant to the exercise of an ISO. A Disqualifying
Disposition is any disposition (including any sale) of such Common Stock before
the later of (a) two (2) years after the date the employee was granted the ISO
or (b) one (1) year after the date the employee acquired Common Stock by
exercising the ISO. If the employee has died before such stock is sold, these
holding period requirements do not apply and no Disqualifying Disposition can
occur thereafter.

     25.  Effective Date and Duration of the Plan.

     A. The Plan shall become effective when adopted by the Board, but no Stock
Right granted under the Plan shall become exercisable unless and until the Plan
shall have been approved by the Company's shareholders. If such shareholder
approval is not obtained within twelve months after the date of the Board's
adoption of the Plan, Stock Rights previously granted under the Plan shall not
vest and shall terminate and shall be null and void and no Stock Rights shall be
granted thereafter under the Plan. Amendments to the Plan not requiring
shareholder approval shall become effective when adopted by the Board;
amendments requiring shareholder approval shall become effective when adopted by
the Board, but no stock Right granted after the date of such amendment shall
become exercisable (to the extent that such amendment to the Plan was required
to enable the Company to grant such stock Right to a particular person) unless
and until such amendment shall have been approved by the Company's shareholders.
If such shareholder approval is not obtained within twelve months of the Board's
adoption of such amendment, any Stock Rights granted on or after the date of
such amendment shall terminate and become null and void to the extent that such
amendment was required to enable the Company to grant such Stock Rights to a
particular person. Subject to this limitation, Stock Rights may be granted under
the Plan at any time after the effective date and before the termination date of
the Plan.

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     B. Unless sooner terminated as provided elsewhere in this Plan, this Plan
shall terminate upon the close of business on the day next preceding the tenth
anniversary of the date of its adoption by the Board. Stock Rights outstanding
on such date shall continue to have force and effect in accordance with the
provisions of the instruments evidencing such Stock Rights.

              Adopted by the Board of Directors on April 28, 2000.
              Amended and Restated on September 6, 2001.

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                                 AMENDMENT NO. 1
                                       TO
                              AMENDED AND RESTATED
                      2000 STOCK OPTION/STOCK ISSUANCE PLAN

     This AMENDMENT is made as of March 31, 2002 (this "Amendment") to the
Egenera, Inc. Amended & Restated 2000 Stock Option/Stock Issuance Plan adopted
by the Board of Directors of Egenera, Inc. on April 28, 2000 and amended and
restated on September 6, 2001 (the "Plan").

     Section 1. Amendment to the Plan. The Plan is hereby amended by deleting in
its entirety the existing Section 5 of the Plan and inserting in place thereof
the following:

     5.   Stock. The stock subject to Options, Awards and Purchases shall be
authorized but unissued shares of common stock of the Company ("Common Stock"),
or shares of Common Stock reacquired by the Company in any manner. Subject to
adjustment as provided in Paragraph 14, the aggregate number of shares that may
be issued under the Plan is 18,250,000 shares of Common Stock. In no event shall
the number of shares subject to all Options, Awards or Purchases under the Plan
at the time of the grant of, and including the shares subject to, any Option,
Award or Purchase exceed 18,250,000 shares of Common Stock (as adjusted pursuant
to Paragraph 14) (a) less (i) the number of shares then subject to options
granted pursuant to the Company's 2001 California Stock Option/Stock Issuance
Plan (as the same may be amended and in effect from time to time, the
"California Plan") and (ii) without duplication of any shares described in the
foregoing clause (i), the number of shares previously issued pursuant to the
exercise of any option granted, or award or purchase under the California Plan,
(b) plus the number of shares originally issued pursuant to the exercise of any
option granted, or award or purchase under the California Plan or this Plan that
are repurchased by the Company pursuant to contractual rights held by the
Company and at repurchase prices not exceeding the respective original purchase
prices (or fair market value of such shares as approved by the Board of
Directors) paid by such persons to the Company. If any option granted under the
Plan or under the California Plan shall expire or terminate for any reason
without having been exercised in full or shall cease for any reason to be
exercisable in whole or in part, the unpurchased shares subject to such Option
or option shall again be available for grants of Stock Rights under the Plan.

     Section 2. Effectiveness. This Amendment shall be effective as of the date
hereof upon the adoption of this Amendment by the Board.

     Section 3. Ratification. Except as otherwise expressly set forth herein,
all terms and conditions of the Plan are hereby ratified and confirmed and shall
remain in full force and effect.

      Adopted by the Board of Directors and Stockholders on March 31, 2002

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                                 AMENDMENT NO. 2
                                       TO
                              AMENDED AND RESTATED
                      2000 STOCK OPTION/STOCK ISSUANCE PLAN

     This AMENDMENT is made as of May 15, 2002 (this "Amendment") to the
Egenera, Inc. Amended & Restated 2000 Stock Option/Stock Issuance Plan adopted
by the Board of Directors of Egenera, Inc. on April 28, 2000, amended and
restated on September 6, 2001, and amended on March 31, 2002 (the "Plan").

     Section 1. Amendment to the Plan. The Plan is hereby amended by deleting in
its entirety the existing Section 5 of the Plan and inserting in place thereof
the following:

     5.   Stock. The stock subject to Options, Awards and Purchases shall be
authorized but unissued shares of common stock of the Company ("Common Stock"),
or shares of Common Stock reacquired by the Company in any manner. Subject to
adjustment as provided in Paragraph 14, the aggregate number of shares that may
be issued under the Plan is 25,250,000 shares of Common Stock. In no event shall
the number of shares subject to all Options, Awards or Purchases under the Plan
at the time of the grant of, and including the shares subject to, any Option,
Award or Purchase exceed 25,250,000 shares of Common Stock (as adjusted pursuant
to Paragraph 14) (a) less (i) the number of shares then subject to options
granted pursuant to the Company's 2001 California Stock Option/Stock Issuance
Plan (as the same may be amended and in effect from time to time, the
"California Plan") and (ii) without duplication of any shares described in the
foregoing clause (i), the number of shares previously issued pursuant to the
exercise of any option granted, or award or purchase under the California Plan,
(b) plus the number of shares originally issued pursuant to the exercise of any
option granted, or award or purchase under the California Plan or this Plan that
are repurchased by the Company pursuant to contractual rights held by the
Company and at repurchase prices not exceeding the respective original purchase
prices (or fair market value of such shares as approved by the Board of
Directors) paid by such persons to the Company. If any option granted under the
Plan or under the California Plan shall expire or terminate for any reason
without having been exercised in full or shall cease for any reason to be
exercisable in whole or in part, the unpurchased shares subject to such Option
or option shall again be available for grants of Stock Rights under the Plan.

     Section 2. Effectiveness. This Amendment shall be effective as of the date
hereof upon the adoption of this Amendment by the Board.

     Section 3. Ratification. Except as otherwise expressly set forth herein,
all terms and conditions of the Plan are hereby ratified and confirmed and shall
remain in full force and effect.

       Adopted by the Board of Directors and Stockholders on May 15, 2002

                                                                              12
<PAGE>

Amendment No. 3 to Amended and Restated 2000 Stock Option/Stock Issuance Plan

     This AMENDMENT is made as of December 19, 2003 (this "Amendment") to the
Egenera, Inc. Amended & Restated 2000 Stock Option/Stock Issuance Plan adopted
by the Board of Directors of Egenera, Inc. on April 28, 2000, amended and
restated on September 6, 2001, and amended on each of March 31, 2002 and May 15,
2002 (the "Plan").

     Section 1. Amendment to the Plan. The Plan is hereby amended by deleting in
its entirety the existing Section 5 of the Plan and inserting in place thereof
the following:

     5.   Stock. The stock subject to Options, Awards and Purchases shall be
authorized but unissued shares of common stock of the Company ("Common Stock"),
or shares of Common Stock reacquired by the Company in any manner. Subject to
adjustment as provided in Paragraph 14, the aggregate number of shares that may
be issued under the Plan is 28,750,000 shares of Common Stock. In no event shall
the number of shares subject to all Options, Awards or Purchases under the Plan
at the time of the grant of, and including the shares subject to, any Option,
Award or Purchase exceed 28,750,000 shares of Common Stock (as adjusted pursuant
to Paragraph 14) (a) less (i) the number of shares then subject to options
granted pursuant to the Company's 2001 California Stock Option/Stock Issuance
Plan (as the same may be amended and in effect from time to time, the
"California Plan") and (ii) without duplication of any shares described in the
foregoing clause (i), the number of shares previously issued pursuant to the
exercise of any option granted, or award or purchase under the California Plan,
(b) plus the number of shares originally issued pursuant to the exercise of any
option granted, or award or purchase under the California Plan or this Plan that
are repurchased by the Company pursuant to contractual rights held by the
Company and at repurchase prices not exceeding the respective original purchase
prices (or fair market value of such shares as approved by the Board of
Directors) paid by such persons to the Company. If any option granted under the
Plan or under the California Plan shall expire or terminate for any reason
without having been exercised in full or shall cease for any reason to be
exercisable in whole or in part, the unpurchased shares subject to such Option
or option shall again be available for grants of Stock Rights under the Plan.

     Section 2. Effectiveness. This Amendment shall be effective as of the date
hereof upon the adoption of this Amendment by the Board.

     Section 3. Ratification. Except as otherwise expressly set forth herein,
all terms and conditions of the Plan are hereby ratified and confirmed and shall
remain in full force and effect.

    Adopted by the Board of Directors and Stockholders on December 19, 2003

                                                                              13
<PAGE>

                               AMENDMENT NO. 4 TO
           AMENDED AND RESTATED 2000 STOCK OPTION/STOCK ISSUANCE PLAN
                                     AND TO
                2001 CALIFORNIA STOCK OPTION/STOCK ISSUANCE PLAN

     This Amendment is made effective as of April 7, 2004 (this "Amendment") to
each of (a) the Egenera, Inc. Amended & Restated 2000 Stock Option/Stock
Issuance Plan adopted by the Board of Directors of Egenera, Inc. on April 28,
2000, as amended and restated on September 6, 2001 and amended on each of March
31, 2002, May 15, 2002 and December 19, 2003 (the "General Plan"), and (b) the
Egenera, Inc. 2001 California Stock Option/Stock Issuance Plan adopted by the
Board of Directors of Egenera, Inc. on September 6, 2001, as amended on each of
March 31, 2002, May 15, 2002 and December 19, 2003 (the "California Plan" and
together with the General Plan, the "Plans").

     Section 1. Section 9B of each of the Plans is hereby amended by deleting in
its entirety the existing Section 9B in each of the Plans and inserting in place
thereof the following new Section 9B:

          "B.  Options granted under the Plan may provide for payment of the
     exercise price to the extent (if at all) provided in the option agreement:
     (i) by delivery to the Company of cash or wire transfer or a check payable
     to the order of the Company in an amount equal to the purchase price per
     share as hereinabove set forth times the number of shares so purchased (the
     "exercise price"); (ii) by delivery of a recourse promissory note of the
     optionee bearing interest payable not less often than annually at such
     market rate for the optionee at the date of exercise as will avoid adverse
     accounting consequences (including without limitation variable security
     accounting treatment under generally accepted accounting principles) and
     otherwise payable on such terms as are specified by the Board in its sole
     discretion, together with cash, a wire transfer or a check payable to the
     Company in an amount equal to the par value of the shares to be issued upon
     exercise of this option; (iii) by delivery to the Company of shares of
     Common Stock of the Company already both owned and vested by the optionee
     for at least six (6) months having a fair market value, as of the date of
     exercise, determined by the Board to be equal in amount to the exercise
     price of the option being exercised; (iv) if a public market for shares of
     Common Stock of the Company at the time exists, the optionee may make
     payment by delivery of an irrevocable direction to a securities broker to
     sell the shares and to deliver all or part of the sale proceeds to the
     Company in payment of the aggregate exercise price therefor; (v) pursuant
     to a program developed under Regulation T as promulgated by the Federal
     Reserve Board; or (vi) by any combination of the above methods of payment."

                                                                              14
<PAGE>

     Section 2. Section 23 of each of the Plans is hereby amended by deleting in
its entirety the existing Section 23 in each of the Plans and inserting in place
thereof the following new Section 23:

          "23. Withholding. The Company shall have the right to deduct from
     payments of any kind otherwise due to the optionee the statutory minimum
     amount of federal, state or local taxes of any kind required by law to be
     withheld with respect to any shares issued upon exercise of Options under
     the Plan or upon the grant of an Award, the making of a Purchase of Common
     Stock for less than its fair market value, the making of a Disqualifying
     Disposition (as defined in Paragraph 24), or the vesting of restricted
     Common Stock acquired pursuant to a Stock Right. The Board in its sole
     discretion may condition the exercise of an Option, the grant of an Award,
     the making of a Purchase, or the vesting of restricted shares acquired by
     exercising a Stock Right on the grantee's payment of such withholding
     taxes. Subject to the prior approval of the Company, which may be withheld
     by the Company in its sole discretion, the grantee may elect to satisfy
     such obligations, in whole or in part, by delivering to the Company shares
     of Common Stock already both owned and vested by the grantee for at least
     six (6) months. The shares so delivered or withheld shall have a fair
     market value equal to such withholding obligation, and shall not be subject
     to any repurchase, forfeiture, unfulfilled vesting or other similar
     requirements. The fair market value of the shares used to satisfy such
     withholding obligation shall be determined by the Company as of the date of
     delivery of such shares to the Company. Notwithstanding the foregoing, in
     the case of a Reporting Person, no election to use shares for the payment
     of withholding taxes shall be effective unless made in compliance with any
     applicable requirements of Rule 16b-3 (unless it is intended that the
     transaction not qualify for exemption under Rule 16b-3)."

     Section 3. Effectiveness. This Amendment shall be effective as of the date
hereof upon the adoption of this Amendment by the Board.

     Section 4. Ratification. Except as otherwise expressly set forth herein,
all terms and conditions of the Plans are hereby ratified and confirmed and
shall remain in full force and effect.

     Adopted by the Board of Directors and Stockholders by Written Consent
                         effective as of April 7, 2004

                                                                              15